This is so strangely sad. Go ahead and write a programming language. Have a weird hobby you clank away on that might not see the light of day. If you burn out on it, that's one thing and that's okay; you've exhausted the medium. Move on to something else you enjoy. Grow for the sake of growing.

Just because something hasn't become big doesn't mean it's a failure. I've labored in dark early hours over paintings and music that will never see the light of day, but it's a vital part of how I express and cultivate myself. My journal.

99% of art is unknown personal projects. Embrace yours. Why be bitter?